Soft-sided insulated containers may be used to transport articles that may best be served cool, such as beverages or salads, or warm, such as appetizers, hot dogs, and so on. Such containers are also used to carry liquids, whether hot liquids, such as soup containers, coffee or tea, or cold liquids such as beer, soft drinks, or other carbonated beverages, juices and milk. The containers are typically made in a generally cube-like shape, whether of sides are of equal length or not, having a base, four upstanding walls, and a top. The top wall is often a lid which opens to permit articles to be placed in, or retrieved from, the container.
In soft-sided insulated containers heretofore, the main closure of the lid has tended to depend on the closing of a zipper, often a zipper running around three sides of a rectangle, with the fourth side being hinged. The lid may rest on a foam lip or bead. When a container of this nature falls over, its resistance to the spilling of liquid through the closure may not be as effective as might be desired. It might be advantageous to have a somewhat tighter seal, such as might be made by stiffer materials in an interference fit. A soft-sided panel would not normally be sufficiently stiff to achieve such a seal. The use of a seal in this nature might also permit the elimination of the main peripheral zipper of the main closure of the container.
Soft-sided insulated containers can also be used as lunch containers or lunch boxes. Such containers may be used by school children to transport their lunch or snacks or other objects to school, to camp, or on field trips. When an object is removed from the container, it may be that it would be convenient to have some place to rest that object. For instance, parents may be concerned about the cleanliness of school lunchrooms and not want their children's food to come into contact with unclean surfaces or surfaces touched by other children. It may also be that one wishes to have a clean surface for placing a piece of fruit or a sandwich, or a surface for cutting a lime or lemon. For whatever reason, it may be desirable to have a place for resting objects. It may also be convenient for that resting place to be firm, such that objects placed upon it may be less prone to wobble or tip, and for that resting place to be washable such that it may be wiped clean with a cloth should drinks or other objects be spilled on it. Further still, it may be convenient for that resting place to be such as may discourage, or limit, the extent to which objects may slide if the surface is not precisely level, as may be the case at a picnic, at a sporting venue, at the beach, or in a moving vehicle such as a school bus.
Furthermore, children are sometimes inattentive with their belongings. It may be desirable to limit the number of items they have to remember to transport to and from school. Providing a working surface on which to place objects that is secured to their lunch container may prevent loss or misplacement of the working surface.